Nope, bookies only want to keep profitable customers, or provide some other upside to them. In the context of bookies they have limited other ways to make money but sometimes their are weird edges that pop-up, like legislated restrictions.

In Australia those running the licensed tote (totaliser) market pools on horse racing can't make the market themselves, they can't legally seed a pool, and since a tote win is a portion of the pool total customers are less inclined to bet on a low value pool, so the markets allow a few high value bettors to seed the pool for them (with generous rakebacks) which they make a net loss on, but has overall positive effect on their business.